Go to simbiology.com get the Sim Blender, it will allow you to hold the pregnancy for as long as you want, or get the Inteenimator witch i think is at the same site, it to can hold pregnancy for as long as you like, and has option to have you sims give birth instantly at any time you want.
before the insim moved there used to be a forum wher ppl set other challenges having to do wit the sims to other ppl can som 1 locate me to this forum it it exists?